The main principle of three dimensional (3D) display technologies is to allow a viewer's left and right eyes to receive images with minor differences, i.e., left and right views. The two views are combined through the analysis of the brain so that the viewer perceives depths of objects in the views, thereby generating a three-dimensional sense.
Early 3D display devices require users to wear corresponding 3D glasses. In recent years, naked-eye 3D display devices receive great attention. There are generally two types of devices used for achieving the naked-eye 3D display: slit grating 3D display devices and micro-lens array display devices. The slit grating 3D display devices are also called parallax barrier 3D display devices. The parallax barrier technology is achieved using a switching liquid crystal display, a polymer liquid crystal layer and a polarization layer. A voltage difference between electrodes of upper and lower substrates of the switching liquid crystal display screen is controlled so that the liquid crystal molecules in the polymer liquid crystal layer are rotated, thereby producing opaque stripes, i.e. parallax barriers. When the switching liquid crystal display screen is turned on, due to the presence of these parallax barriers, views that are seen by the left eye can be seen only by the left eye and the right eye is shielded; and views that are seen by the right eye can be seen only by the right eye and the left eye is shielded. When the liquid crystal display screen is turned off, no parallax barrier exists in the display panel, and thus the 3D display device is converted into a normal 2D display device.
At present, the naked-eye 3D display devices in the related art requires additional 3D gratings capable of realizing parallax barriers in front of the display panel, which is not conducive to the thinning and lightening of the three-dimensional display devices.